Boiler-water-level automatic control apparatus



Feb; 23 ,1926;

L. c.- DAVIS BUILER WATER: LEVEL AUTOMA'II C CONTROL APFARATUS Fild April 5, 1925 Patented Feb. 23, 1926.

1,57% T ()F Q Fifi.

LEWISC. DAVIS, or BALTIMORE, MARYLAND.

BOILER-WATER"LEVEL AUTOMATIC CONTROL APPARATUS.

Application filed April 3,

To all whom it may concern:: a

Be it known that I, Lnwls C. DAVIS, a citizen of the United States, residing at Baltimore, in the county of Baltimore City and State of Maryland, haveinvented certain new and useful Improvements in Boiler-lV-ater-Level Automatic Control Apparatus, of which the following is a specification. i

.This invention relates to automatic water level and supply controllers and emergency indicators for steam boilers. I

The objects of the present invention are, to provide a very sensitive apparatuswhich will act quickly and delicately in supplying and shutting off the water supply; to provide an apparatus which will. control the supply of water in such manner that the water will be admittedin small quantities and with great frequency and will guard'against a large body ofwater being supplied at any one time in order to avoid cooling of the whole body of water in the boiler;-to provide a pressure controlled apparatus as distinguished from a thermostatic control; to provide means for sealing the pressure element, water, inthe generators of the apparatus; to provide easy means for replenishing the pressure element, water, in the generators from the boiler water; to provide a control apparatus wherein the pressure generators will require refilling only at long intervals; to provide quick, simple and certain means for venting the pressure generator systems; toprovide simple and cheap and quickly replaceable diaphragms in the control apparatus; ,to provide av construction wherein the diaphragins will be so locatedas to be guarded against the action of heat; to provide a lever and connecting meansoperated by a diaphragm for operating a lever or other operative part, which may be connected to a water'supply valve for supplying water to aboiler or battery of boilers, or to a steam valve for governing the supply of steam to the steam motor of a water pump, or to an electrical switch or other element for the purpose in view; to provide a second lever as an emergency device, which, on the continued lowering'ot the water level, will be actuated by an independent pressure generatorto sound a signal or bring signal or other indicating means into operation and to pro-' vide means, which maybe said second lever, operated by said independent pressure chambers 5 and 6 being 1925. Serial No 20,526.

generator, for also operating said water con trol means, all as hereinafter more particularly set'forth, described and claimed.

In the accompanying, drawing, illustrating merely one embodiment or arrangement otnry invention, but without any wish, or desire to be understood as being limited thereto: Figure l a boiler with apparatus embodying my in vention applied thereto;

Figure 2, a top plan view pipes or inclined chambers 5 pass T, with the water tubes 2 audit connected of the upper and 6 and bycolumn connecting thereto and broken represents a front elevation of awav, and showing the pressure generator tubes 8 ant 9 combined therewith; and

lligure 3, a longitudinal sectional view through the diaphragm chambers 13 and 14 and connecting pipe 15, showing the tubes 8 and 9 and the supply pipe 16 broken away. i e

, i ihile one'ein-bodimcnt of my invention is shown and described in detail, the pipes or shown as arranged with ra common axial line, it is to be under stood that, itis not essential that said chamhers 7 should be thus; arranged, it being suliieient it th chamber 6 be arranged on a lower level than chamber 5 and that there be an unobstructed passage from one to the other, and so long as this feature is regarded they may be arranged in any oneoi a number of ,ditierent ways. The actual form or appearance otthe apparatus is governed in large part by the boiler, the arrangement of the parts being such as to conform to the space available, as will be obvious to one familiar with the art.

Referring now indetail to the drawings,

A indicates a conventional boiler, B the" usual watersupply pipe thereof'having a hand valve .6, D. the usual water column having the .usual indicator "or sight glass or gage 15 indicates a whistle mounted on the top of the water column D and adapted to be blown by steamtrom the top of the waterecolumn D and the top or dome of the boiler A upon the proper actuation of the whistle lever (it; H indicates a pipe leading from the top of the boiler A to supply steam to a steam engine, not shown, tooperate a water pump, not shown, of any usual con-.

struction, to force water through the supply pipe 'B so long as the valve operated by the the space available adjacent lcverl. remains in open position; and. J represents a weight hung on lever I for holding it normally in closed position; Of course, any equivalent means, having the same general function, that is, closing the valve operated-by lever I amt ma'ii'ita'ining it normally closed, may be substituted for the weight- J.

The water column D in usual practice'is provided with three test pet-cocks, so that in case the indicator glass or gage 1f should break the operator could cut it out, and still tell as to the level ot thewater in the boiler by the test pet cocks and so continue the boiler in operation with satety. These pet cocks are arranged at three different levels to indicate normal water level at pet-cock end of the head of a T-eoupling 1 into or onto its bore or nipple in or on the water column D, screwing the pet-cock L on the other end of the. head of said T coupling 1, and connecting the small pipe or preferably copper tube 3 to the end of the stem, and to similarly connect the small pipe or pretera'bly copper tube 4 by means of a T-coupling Qbbtween the water-column D and the petc'oeltM. so that said tubes or pipes 3 and t at all times have communication with the il' 'teriorot said water-column D at the resne'ct ive. l evels ot the .said PQt-CQCRSJIJ and M' and with the interior of the boiler through the said water-column D. which t tan g'edflat or near its'top and bottom, respectively. with the'interior of saidboiler hvni' ians ot tubes'. or pipes as usual." n pipe or chamber 5,,preterably lying in a' very slightly inclined plane and having no interior portion at a higher level than tht' interior of the coupling 1, is connected to the latter by the preferably substantially horizontal tube or pipe 3 as shown, and a plpt 'o'r chamber 6 having its lowest portion preferably in the same, and iniio case below the"hori/iont al plane as the coupling 2,.and meter-may arranged at a slight inclination, isconnected to th'elatter by'tli'e pipe or tube 4; which" s'prete'ably horizontal, and the intbi iorsot" the pipes or chambers 5 andG are in am-maanic'atroa with each other through the tubular: means or by-pa's's' 7, which may be'ofelongatedU 'shape, and of "clt 11' "part isat a'higher' level than the p 7 part civil-51111561 5 and no part at a lower level than tlle'highest part of chamber 6,itsarrangement being such'that there will be a slight drop from 5 to 6 so that water may drain by gravity from 5 to 6 and be replaced as itrecedes by steam.

The function of this by-pass 7 is to permit of the draining of water-from chamber to chamber 6, so that as the water level in the boiler 'fa'lls'the water in the chambers 5 and 6 may drain from the chamber 5 to chamber (Sand from chamber 6 through pipe or tube a back into the water column'D, the recession-0t the water allowing steam, pass-- ing through coupling 1 and tube 3 to progressively enter the ehan'lbers 5 and (5 .as the water level falls to the point where the water level in column D tails below cou pliiig :2 and pipe or tube l,when all the water will be drained from the chamber 5, by-pass 7 and chamber Sand they will be filled with steam as above explained.

Of course, as the water level progressively falls a progressively. larger surface of the generatortube 8 in chamber 5 will be exposed to the action of steam in chamber 5 to heat-the tube 8 and vaporize some of the contents thereof, and this applies also to chamber 6 and generator tube 9 as the water continues to fall, should the primary generi ator be out of order, untilthe water level has dropped below coupling 2 when all water will have drained through pipe or tube 4 from the chamber 5, by-pa'ss 7 and chamber 6 back to tl1e,\vater-column D or the boiler, when there will be a freeand unimpeded circulation of hot steam through the'chambers Sand 6, that is to say, through tube 3, chamber-15, by-pass chamber 0 and back through pipe 4, resultingin a very rapid generation otsteain and pressure-"in the" generator tube 9 with consequent quick responsiveoperation of the lever 25, pulling on the cable 28 to sound the Whistle and simultaneously pulling, on the cable' 27 to pull theleverQZ and so pull oncabl -24 to actuate lever I. c. l .v c

Of course, IWhenj thewater level isflappreciably below coupling 1, but above coupling 2, the Water vvillhave drained par: tially from chamber 5, by-pass. 7 and chamberjfi, so that, whilethe chamber 5 might be free of water, or partially free thereof, leaving the. generator tube therein exposed, or partially exposechto' the action of thesteam', there would be water'in the tube 4 andin the chamber 6 and also in by pass 7,]th'us" blocking a free circulationof steam through the tube 8, chamber 5, bypass 7, chamber (Sfand back by tube' to the water column D, and the boiler thus pre venting the heating action of the steam on the generator tube gin} thechamber 6 to generate steam therein so long as the Water level iii iebo'iler' remains ata point above are lli'gitst aint oftlie C ambe s, In S c cofiditions', so long as theehamber 6 is complctely full of water, the steam will not enter, as steam, therein, but will act only to heat the generator tube 8 and its conten s to generate steam therein, and in so doing will yield up its heat to the tube 8 and its contents and will thereby be condensed. In other words, in these circumstances, there will be a continuous condensation of the steam in chamber 5 and a corresponding generation of pressure in the tube 8 due to the heating thereof and the generation of steam therein, the condensate returning to the boiler with the water through the lower pipe or tube l.

The pipe or chamber 5 will have its ends scaled or plugged or otherwise closed and will preferably be of relatively large internal diameter, preferably three-fourths of an inch in internal diameter, and has extending through it a tube 8, preferably of copper, and preferably one-half inch in external diameter, said tube 8 being normally out of communication with the interior of chamber 5 and having its ends extend beyond the closed ends'of chamber 5, asshown. The pipe or chamber 6 will preferably be the same size and construction as the chamber or pipe 5 and hassimilarly extend in through it and beyond its ends a tube 9, also preferably of copper and preferably of three-eighths inch external diameter, be-.

ing appreciably smaller in diameter than. tube 8, in order to provide a greater space or chamberfor a greater body of heating medium, steam, and a smaller space for a smaller column or bar of water to be heated by the steam in order to expand and generate pressure with greater rapidity in the emergency pressure generator tube 9. 1

The adjacent ends of the tubes 8 and 9 are connected by a coupling lfprovided with a valve 11 for normally preventing communication between said tubes 8 and 9, while permitting such communication between said tubes for purposes of filling or refilling them.

The other end of tube 8 is bent clownward and coupled to nipple 12 of diaphragm chamber 13, while the other end of tube 9 is similarly bent downwardly and similarly connected to the nipple 12 of diaphragm chamber 14- l v A. hand operated valve controlled vent 17 is interposed in the tube 8, and at its highest point, between the chamber and nipple 12 of chamber 13.

A tubular rod or pipe is interposed between, and connected to, the "diaphragm chambers 13 and 1 1, being sealed off from, and out of communication with, chamber 13 by means of a suitable plug or other equiva- "lent means, andnormally sealed off from communication with chamber 14 by means of the valve or turn-plug 29. This rod or plpe 15 serves to maintain the spaced rela- V levers 22 an d.-

preferably approximately twice tion of the chambers 13 and 1 1 and. the

23 and also to establish communication between pipe 16 and chamber 14.- for purposes of refilling. However, both of these functions may be accomplished in any one of avarie'ty of ways, the rod or pipe 15 extending from tlie'chan'lbei. 1? to the chamber 11 is not cssential'lt'or ynn'poses of spacing this may be accomplished by securing against a wall or in. any other obvious mannor, and any valve controlled means of comn'lunicatioi'i between pipe 16 and chamber l l may be substituted for that of the structure shown;

The interior of pipe 15 is in communication with chamber 6 by means of connecting pipe 16, so that, pipe 15 being at a lower level than chamber 6, pipe 15 is always full of water. small drain cock 18 for ing 01f sediment from be necessary, or for draining the water from the pipes 15, 16 and from the generator tubes 8and9.

In each diaphragmchamber 13 and 14 is suitaliily held in usual manner a preferably the purpose of drainrubher diaphragm 1.9 which bears against the foot20 of a rod 21 working through the outer end of said diaphragm chamber, the rod 21 of chamber 13 hearing against the lower end of lever 22 having a'short operating arm and adapted to turn it on its pivot 32 mounted in its arm 33 to pull on the cable 24 passing about pulley 25 to swing lever I upward tomove its valveto open position to cause water to besupplied'to the boiler; and the rod 21 of chamber 14; bear- 111g against-the 'lever23, havingan arm of theoperating arm of lever 22, or'pull on cable 24: by cable 27 and lever 22 if the latter should fail of operation by the diaphragm of its diaphragm chamber 13, and to pull on cable 28 to operate the whistle or other warning signal to notify the operatortha't the normal water controlling pressure generator was out" of order.

erating'and actuating tem, the tube 8, pipe 5 and diaphragm chamber 13 and operative partsconstituting the normal. water control pressure generating system. and the smaller diameter tube 9, p pe 6 and dlaphragm chamber 141. and operative partsconstituting the emergency water control and signal ope 'ating pressure generating system, the two systems being adapted to be temporarily put in communication with the interior of the pipes 5 and 6 and by-pass 7 by valve 29 and with each otherby valve 11 for thepurposes of flushing the length to operate This pipe 15 is provided with a;

time to time as may and replenishing the water in the two pressure generating systems, the valve oi the airvent 17 being opened at the same time to ensure the escape of all air from both pressure generating systems.

To start up operation, assuming that the boiler is empty and the invention has just been applied thereto: I

The boiler will be filled with water and during such periodthe valve 11 and valve 29 and valve of air-vent 17 will be left open, so that ZlSitllG boiler fills-and the water level rises in the water-column to and above coupling 2 water will flow along tube orpipe to chamber ('3, through the latter to pipe 16, to pipe 15, through valve 29 to diaphragm chamber 14, up tube 9, through valvell'to tube 8, to air-vent 17, down pipe or tube 8 to diaphragm chamber 13, filling the latter, any air in the tubes 8 and 9 of diaphragm chambers 13 and 14 of the two pressure generatin s stems 'esca'in throu h vent 17.

O'tcourse, as soon asthe pipes 15 and 16, the diaphragm chamber 14 and curved outer end of tube 9 are fillednthe chamber 6, by pass 7 and chamber 5 will be filled progressively and to the same level as the water rises simultaneously with the filling of the remained of tube 9 and tube 8, until the water level in the water-column D and boiler rises slightly beyond or above the top of coupling 1, when the supply of water is'to be shut off. Thereafter'the valves 11 and 29 and the valve of air-vent =17 will beleft open for a short period, somewhat lessthan a minute will sufiice, to becertain that the diaphragm chamber 13 is filled and all air is vented from the two pressure systems.- The valves 11 and 29 and valve of air-vent 17 will then be closed, resulting in sealing the water in each pressure .Igenera'tor tube from that in the other pressure generator-tube, ftrom the atmosphere, and from the Water in theapipe 15. I A *2 The *fire will then be started up and as the water is heated and steam generated the level of the water will drop until the end at coupling 1 is, uncovered, allowing steam to pass -th-erethroug-h and through tube 3 into the chamber 5 as thewater therein recedes with the lowering et-the waterle've'l in the column D, such steam heating the water in the tube '8 andturning some 0f it into steam with resultant expansion and creation or pressure in the tube Sand diaphragm chamber 13, thrusting-outwardly or endwise against its diaphragm 19 and through the diaphragm 19 againstfoot 20 of its rod 21, which rocks lever 22 to pull on cable 24 to start the water supply. As the water is supplied it, as'its level rises and so :fillsthe chamber 5, excludes or driv'esout the steam and cools the water "in tube 8, con- "(lensing the vsteam therein and so reducing ahe pressure therein, iallowing -the 'lever 22,

by Letters Patent is r and the lever I of the water control valve to drop back to normalclosed position under the influence of weight J or equivalent means.

' -Howcver, assuming, "for instance, that the diaphragm 19 in chamber .13 has given Way or' been ruptured,-so rendering the normal water control pressure generating system noperative, the water level will continue to fall, and the level of the water in chamber 5, bypass? and chamber -6 in accord therewith, allowing steam to work around through bypass 7 into chamberG, when it will act to heat quickly the smaller copper .t ube 9 and to generate steam therein with consequent rapid generation of pressure in the emergency water control and signalling pressure generating system, resulting in operating the lever 23 to, through cables 27 andQa, operate lever I and to pullon cable 31 to operate the whistleor other signal.

-Since, thetubes and: 9 and their diaphragmachambers '13 and 1 k respectively are hermetically sealed there is no opportunity for any appreciable loss 7 of contents by means of=evaporation, so that they require --re fill ng only at very infrequent intervals.

In use I'have found that refilling of such pressure generators once a month was sufficient over a period of a numberof months.

In applying the diaphragms 19 they will not be stretched, buton the contrary will be left sufliciently slack so that they may flex,

without stretching, torthe full amount of their deformation under greatest pressure conditions, in order that their material be not called upon to actively resistthe pressure generated, but merely to act as a flexible seal-for the endof the chamber there- "by prolonging their period of usefulness. .'I-Iav.ing 1 thus described my invention,

:ivhaty-I-claim as new and desire to secure T1.In -a b01161 water level iau'tomaticcontrol apparatus, a chamber, means forming communication between the interior of the boiler and said chamber and means for forming communication between the boiler and-said chamber at :a'lower level so-that as the water level lowers Yinthe boiler the water :lll' said chamber, will draintherefrom, 1n ac cordance with the water level, through the latter means, allowing: steam to enter said chamber from the 'boilcr through the former means, and soithat as the water level rises the inflow of water through the second mentioned means will-drive the steam from said chamber through th e: first imentioned means, incombination with a container normally sealedand extending in said chamber, an

operative' agerit in said container of such nature as "to be actedupon the heat of the steam thereon and so caused to expand to generate pressure.;in-said container and to be condensed hack to normal byiimmersion of the container in water of normal boiler temperature, means actuated by the expansion of said agent in said container for causing the supply of water to the boiler until the water level has been raised suitficiently to drive the steam out of said chamher and act on said container to cool the agent therein to reduce the pressure therein, and means adapted to put said chamber and said container temporarily in communicat on to fill said container.

2. In a boiler water level automatic control apparatus, a chamber, means forming communication between the interior of the 'Jciler and said chamber, and means forming communication between the interior of the boiler and said chamber at a lower level so that as the water level lowers in the boiler the water in said chamber will drain therefrom, in accordance with the water level, through the latter means, allowing steam to enter said chamber from the boiler through the former means, and softhat as the water level rises the inflow of water through the second mentioned means will drive the steam from said chamber through the first mentioned means, in combination with a container normally sealed and eX- tcnding in said chamber, water in said container, means actuated by the expansion or the container water when under the influence of steam in said chamber for causing the supply of water to the boiler until the water level has been raised sufficiently to drive the steam out of said chamber and act n said container to cool the water therein to reduce the pressure therein, means adapted to put said chamber and said container temporarily in communication to fill said container, and means for venting the air trom said container as it is being lilled with water.

3. In a boiler water level automatic control apparatus, a primary chamber, a steam supply pipe forming communication between said chamber and the boiler, a tube extending through said chamber and sealed therefrom and adapted to contain water, a diaphragm chamber in communication with said tube and a diaphragm therein and closing the same, said water in said tube being adapted to be vaporized by steam entering said chamber through said pipe to generate pressure in said tube and diaphragm chamber to cause movement of the operative portion of the diaphragm, and means operated by said diaphragm to control the boiler water supply, in combination with an emergency chamber 1 arranged at a lower level than said primary chamber, a by-pass forming communication between said chambers, said chambers being of the same internal diameter, a pipe forming communication between the lowest portion ofsaid emergency chamber and the boiler on operate the boiler water a level at leastaslow as-said portion, an emergency tube extending through said emergency chamber, sealed therefrom, of smaller diameter than the first mentioned tube, and adapted to contain water, a dia phragm chamber in communication with said emergency tube, adiaphragm therein and means adapted to be operated by the movement of said last mentioned diaphragm to supply means and means, said tubes from each other, establishing comto operate said signaling being normally sealed oil and means for temporarily munication between said tubes and between said tubes and chambers and between said tubes and the atmosphere, for the purpose of refilling said tubes and diaphragm chambers with water and for venting; all air from said tubes and said diaphragm chambers, said diaphragm chambers being arranged at points belowthe lowest portion of said emergency chamber in order to protect the diaphra 'ms against the action of heat. a

4. In a boiler water level automaticcontrol apparatus, a primary chamber, a steam supply pipe forming communication between said chamber and the boiler, a tube extending through said chamber and sealed therefrom and adapted to contain water, a diaphragm chamber in communication with said tube and a diaphragm therein and closing the same, said water in said tube being adapted to be partially vaporized by steam entering closing the same, a signaling means, 1

said chamber through said pipe to generate gency chamber arranged at a lower level than said primary chamber, a by-pass forming communication between'said chambers, a pipe forming communication between the lowest portion of said emergency chamber and the boiler on a level at least as low as said portion, an emergency tube extending through said emergency chamber, sealed therefrom, of smaller diameter than the firs mentioned tube, and adapted to contain. water, diaphragm chamber in communication with said emergency tube, a diaphragm therein and closing the same, a signaling means, means adapted to be operated by the movement of the lastinentioned diaphragm to operate the boiler water supply means and to operate said signaling being normally sealed off from each other, and means for temporarily establishing communication between said tubes and between said tubes and chambers and between said tubes and the atmosphere? for the purpose of refilling said tubes and diaphragm chambers with water and for ventingall air from means, said tubes said tubes and. said diaphragm chambers.

In a boiler water level automatic, control apparatus, a primary chamber, an emergency chamber arranged below said primary chamber, a by-pass establishing continuous communication between said chambers, tubular means. forming communication between said primary chamber and the boiler at the normal boiler Water level, and tubular means forming communication between said, emergency chamber and the boiler at a lower level, in combination with a primary con.- trol means comprising a tube having a portion extending through said primary, chamber, an active agent sealed in said means and partially contained in said tube and 0t such nature as to be expanded by the heat of steam in said primary chamber to gen crate pressure in said means and cooled by Water as it rises in said primary chamber to eliminate pressure in said means, and water supply means controlled by, the variations of pressure in said means 3 an emer-.

gency control and signaling means comprising a signal, a tube having a portioirextending through said emergency chamber, a similar active agent sealed in the emergency means, a movable part actuated by the varia- .tlons. of. pressure in said emergency means,

a supplemental element connected to said movable part to operate the Water supply means, and meansconnecting. said movable part to said signaling means; the tubes of said primary and emergency control means. being sealed: oil from each other normally so that their active agents will normally act independently of each other, means for establishing con'nnunication between said tubes, and between. said. tubes and said: chambers. for refilling the primary and emergency controlmeans, and means for venting the air from. said primary and emergency control means through the highest point o t said tubes when. said tubes are in'communication with each other. 7 V

In testimony whereof, I have signed my name to. this specification at \Vashington, D; 0., this 3rd day of April, 1925.

LEWIS G. DAVIS. 

